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171.
172.
Midwife crisis?     
While most pressure groups have been asking for more for their part of the health service, AIMS has been demanding less for the last 30 years. In the first of two articles on maternity services, Beverley Lawrence Beech and Jean Robinson explain why obstetricians should take a backseat role to midwives.  相似文献   
173.
The pars tuberalis (PT) of the pituitary gland shows dense binding of melatonin and consequently this region may be involved in modulating seasonal reproduction. Oestrogen is well established as a critical gonadal steroid in controlling seasonally via its ability to alter luteinizing hormone (LH) release. Using immunocytochemistry techniques with antibodies specific for the oestrogen receptor (ER) and the ovine βLH (oβLH) subunit, we have identified large populations of ER-immunoreactive (-IR) and LH-IR cells in the anteroventral region of the ovine PT. In contrast, few ER- or LH-IR cells were identified in the anterodorsal or posterior regions of the PT. Double-labelling experiments revealed that all ER-IR cells in the PT are also immunoreactive for LH. These results show that cells immunoreactive for the ER are concentrated in the anteroventral aspect of the PT and that these receptors are located in the nuclei of the PT gonadotrophs. These results suggest that the anteroventral PT, a region which also expresses high melatonin binding, may be a site of integrated oestrogen and melatonin action on LH secretion from the PT.  相似文献   
174.
This study was conducted to determine whether helium-neon laser would alter the regeneration process of a crushed nerve. If a biostimulating effect of laser irradiation was found, additional support would be provided for its use in the management of peripheral nerve injured patients. The peroneal nerve in both hind limbs of 12 female New Zealand White rabbits was crushed. The randomly selected limb received laser treatments daily for 15 days. Functional regeneration of the nerves was measured by nerve conduction amplitude performed prior to crush and every third treatment day thereafter. A split-plot ANOVA used to compare the difference in the amplitudes of the evoked motor potentials demonstrated a significant interaction (p < .01) for leg x day, indicating a significantly different pattern in measured amplitudes between treated and nontreated animal limbs over the course of the 15 days following lesion. J Orthop Sports Phys Ther 1992;15(5):209-214.  相似文献   
175.
176.
A method for the determination of 6,17-dimethylpregna-4,6-diene-3,20-dione (medrogestone) in serum is described using high-pressure liquid chromatography with UV detection. Interfering substances in human or dog serum blanks were removed selectively by reaction with oxalyl chloride followed by an aqueous alkaline borate "wash" of the extract. The method is specific for medrogestone and, based on 5 ml serum, has a limit of detection of 2 ng/ml.  相似文献   
177.
Summary Naringenin (4,5,7-trihydroxy-flavanone) inhibits the accumulation of glycine, -methyl-glucoside, p-amino-hippurate and N1-methyl-nicotinamide in dog renal cortex slices. It also inhibits oxygen consumption by this tissue. Since the sensitivity of amino-acid uptake to the drug is less than the sensitivity of oxygen consumption, the inhibition of this transport might be secondary to an effect on intermediary metabolism. The inhibition of PAH uptake occurs at a lower concentration of the drug, and so naringenin may affect this process at the membrane level.Naringenin inhibits the transport of sugars and amino-acids by dog, guinea-pig and rat small intestine. Both steady-state accumulation and initial rates of entry are affected. Amino-acid uptake is depressed both in the presence or absence of sodium ions. The inhibition is reversible provided short contact times are employed. According to kinetic analysis, naringenin appeared to be a fully non-competitive inhibitor of phenylalanine influx. Examination of the unidirectional transmural fluxes of phenylalanine across guinea-pig intestine revealed that only the mucosal-serosal flux was affected, and then only if the flavanone was added to the solution bathing the mucosal face of the tissue. Naringenin does not inhibit mucosal Na+-K+-ATPase, but it does alter the intracellular ion concentrations.Although some of the results can be explained in terms of an effect of naringenin on metabolism, others can not. It is argued that naringenin has a direct action on cell membranes.Some of these results have been presented to the Physiological Society and a short report has appeared in their proceedings (Robinson, 1979)  相似文献   
178.
A nearly fatal allergic reaction to intratumor BCG injections was associated with a complete remission of recurrent malignant melanoma. Clinical course and histologic sections suggested both anaphylactic and Arthus reactions. The occurrence of reactions at BCG injection sites as well as at uninjected sites of tumor suggests common BCG and melanoma antigens. The management of events involved in this often fatal postimmunotherapy complication involves the early administration of parenteral fluids, antituberculous therapy, antihistamines, and possible steroids. The prophylactic use of antihistamines and an in-hospital administration of intralesional BCG immunotherapy are strongly suggested. In the future, prophylactic INH may prove to be both therapeutically efficacious and protective against infectious complications.  相似文献   
179.
A continuous cell culture line was established from a bone marrow metastasis of small cell anaplastic carcinoma of the lung. The cultures were characterized by light and electron microscopy, and an unusual concentric arrangement of cells was observed, both in sectioned material from the patient's tumor and from the cell cultures. The cells had two types of specialized cell junctions and contained secretory-like granules of the type described in neuroendocrine cells. Lactic dehydrogenase isozyme patterns were the same as those observed in normal human serum, and the karyotype revealed the presence of several marker chromosomes. Vasopressin was present in the cells and secreted into the culture medium in the absence of neurophysin, as shown by the immunoperoxidase technique and radioimmunoassay. Oxytocin was also absent from cells.  相似文献   
180.
Hypothalamic neurons secreting vasopressin and neurophysin.   总被引:2,自引:0,他引:2  
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